1. Field of the Invention
The present invention relates to a package for an integrated circuit.
2. Description of Related Art
Integrated circuits are typically housed within a package that is soldered to a printed circuit board. Some packages contain a heat slug to facilitate the removal of heat generated by the integrated circuit. The package may also contain a number of discrete capacitors which filter the power and/or signals provided to the integrated circuit.
FIG. 1 shows a top surface of an integrated circuit package 2 of the prior art. The package 2 has a rectangular heat slug 4 that is surrounded by a number of through hole vias 6. The vias 6 provide interconnect to a plurality of lands located on the opposite bottom surface of the package. The lands are typically soldered to an external printed circuit board. The number of lands for the package are typically limited by the number of vias 6 that can be formed in the package 2.
Mounted to the top surface of the package are a number of capacitors 8. The capacitors 8 are mounted to surface pads 10 located on the top surface. The capacitors 8 and accompanying pads are relatively large and occupy valuable space on the top of the package. Some of the vias 6 must be eliminated to provide room for the capacitors. Eliminating vias reduces the number of lands and the pin throughput of the package. Adding more capacitors to the package would necessitate the elimination of more vias and further reduce the output pins of the package. It would be desirable to provide a package design that can add capacitors without eliminating more vias and corresponding lands.